On Fri, Jan 4, 2019 at 7:06 AM John Clark <[email protected]> wrote:
> On Thu, Jan 3, 2019 at 3:58 AM Bruce Kellett <[email protected]> > wrote: > > >> *> The 't' in your formula above is the coordinate time, not the proper >> time. * >> > > What the hell are you talking about? If I travel from event A to event B > and use the formula x^2 + y^2 + z^2 -(ct)^2 where x,y,and z are the > differences in spatial coordinates I observe and *t is the proper time* > it took for me to make the trip I will get an invariant. If you also > travel between event A and B but use a different path you will get entirely > different numbers for x, y and z and you will get a different number for *the > proper time t,* but when you plug in your numbers into x^2 + y^2 + z^2 > -(ct)^2 you will get the exact same value I do. > You clearly do not know =what 'proper time' is. > > >> *> The proper time is defined as the time kept by a perfect clock >> travelling on a geodesic.* >> > > No it is not! The proper time is defined as the time measured by a clock > along ANY line through spacetime and it doesn't matter a hoot in hell if > that line is a geodesic or not. And you said "*Proper time is the > distance through spacetime*" but every book on physics on the planet will > tell you that the distance through spacetime is an invariant; but proper > time is NOT a invariant, > Wikipedia thinks that it is.....at least in non-curved space-times. > different observers can have different proper times, even you know this > because you said "*two different orbits of the Earth, both geodesics, can > coincide at a pair of events. They will measure different proper times > between those events*". So your ideas are not self consistent but then > they had to be, spacetime distance and proper time aren't even in the same > units. > > The reason you need both a odometer and a clock in your car is that they > measure different things. And no matter how hard you try you're never going > to be able to subtract seconds from meters, so why are we still arguing > about this when it's obvious you're wrong? > Have you never heard of natural units, units in which c = 1? Bruce > > *And a geodesic is the path along which the rate of time is constant.* >> > > What the hell?! Obviously the rate of time is always constant for any > observer in the same reference frame as the clock regardless if the path is > a geodesic or not, it will always change at the rate of one second per > second . It doesn't take a Einstein to know that. > > John K Clark > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/d/optout.
